Roofing product including recycled roofing material and method of forming the same

ABSTRACT

A roofing product can include a base material and a first coating including a bituminous material. In one embodiment, the first coating can include recycled roofing material adjacent to the base material. The recycled roofing material has a first recycled roofing content of less than 40 weight %. In another embodiment, the roofing product can include a base material and a first coating including a bituminous material. The first coating is adjacent to the base material. The roofing product can also include particles along a first exposed surface of the roofing product, wherein the particles include recycled roofing material particles. Methods of forming such roofing products are also disclosed.

RELATED APPLICATION

This is related to and claims priority under 35 U.S.C. §119(e) to U.S.Patent Application No. 61/257,702 entitled “Roofing Product IncludingRecycled Roofing Material and Method of Forming the Same” by Kalkanogluet al. filed on Nov. 3, 2009, which is assigned to the current assigneehereof and incorporated herein by reference in its entirety.

FIELD OF THE DISCLOSURE

The present disclosure relates to roofing products and methods offorming roofing products, and more particularly to, roofing productsincluding recycled roofing material and methods of forming the same.

RELATED ART

Roofing products can be in different forms, such as shingles ormembranes. The roofing products can include a base material and abituminous material. The base material can include wood, a woodderivative (e.g., paper), fiberglass, organic fibers (e.g., polyester),or the like. Conventionally, the bituminous material can includeasphalt, a filler, and potentially a plasticizer. A variety of fillershave been used including limestone, talc, fly ash, coal fines, or otherrelatively inert materials. Limestone has been mostly commonly used asfiller in roofing products due to its relatively low cost and itscompatibility with a wide variety of materials used for roofingproducts. Traditionally, recycled roofing material has not been used inroofing products.

Currently, recycled roofing materials are being considered for use informing new roofing products. Methods have been proposed to rejuvenatethe bituminous material and to remove roofing nails from the recycledroofing material. Regardless whether a roofing product includes or doesnot include recycled roofing material, the roofing product must still beable to withstand the rigors of shipping and handling, installation, andexposure to outdoor environments for several years. Further, duringstorage, shipping, handling, and until finally installation, the roofingproduct should be able to be in contact with another roofing productwithout the roofing products prematurely adhering to each other.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments are illustrated by way of example and are not limited in theaccompanying figures.

FIG. 1 includes a process flow diagram illustrating an exemplary methodof forming a roofing product.

FIG. 2 includes an illustration of a particle size distribution ofconventional limestone filler within an asphalt coating.

FIG. 3 includes an illustration of a particle size distribution ofrecycled roofing material.

FIG. 4 includes an illustration of a cross-sectional view of a roofingproduct in accordance with an embodiment.

FIG. 5 includes an illustration of a cross-sectional view of a roofingproduct in accordance with another embodiment.

FIG. 6 includes an illustration of a cross-sectional view of a roofingproduct in accordance with a further embodiment.

FIG. 7 includes a process flow diagram illustrating an exemplary methodof forming a laminated roofing product.

FIG. 8 includes an illustration of a cross-sectional view of sheets ofintermediate roofing product before the sheets are laminated togetherinto a laminated roofing product in accordance with an embodiment.

FIG. 9 includes an illustration of a cross-sectional view of a laminatedroofing product formed after laminating the sheets of FIG. 8 andcompleting a finishing operation in accordance with another embodiment.

Skilled artisans appreciate that elements in the figures are illustratedfor simplicity and clarity and have not necessarily been drawn to scale.For example, the dimensions of some of the elements in the figures maybe exaggerated relative to other elements to help to improveunderstanding of embodiments of the invention.

DETAILED DESCRIPTION

The following description in combination with the figures is provided toassist in understanding the teachings disclosed herein. The followingdiscussion will focus on specific implementations and embodiments of theteachings. This focus is provided to assist in describing the teachingsand should not be interpreted as a limitation on the scope orapplicability of the teachings.

Before addressing details of embodiments described below, some terms aredefined or clarified. The term “abrasive particle” is intended to mean aparticle having a hardness at least as hard as a ceramic base materialused or to be used within the same roofing product.

With respect to dimensions, the length and width are dimensions thatextend along the principal surfaces of a roofing article. The width ismeasured in a direction that would extend vertically along a roof whenthe roofing article would be installed, and the length is measured in adirection perpendicular to the width and along the roof. The length andwidth can be substantially in a same plane, such as a plane of anunderlying roofing support structure when the roofing article would beinstalled. Each of the length and width is greater than the thickness.

The term “actinic radiation” is intended to mean radiation that isintentionally performed, or directed at or on a surface or portion ofthe roofing product, and results in cross-linking, oxidation, anotherchange, or any combination thereof, of a surface or other portion of theroofing product to attain a specific property. The term “actinicradiation” does not include incidental radiation, such as sunlight,fluorescent lighting, or other lighting at a storage facility or otherbuilding, or other similar radiation during the manufacture, storage,shipping, or installation of the roofing product.

The term “perimeter volume” is intended to mean a volume generallydefined as contained by outer surfaces of an object. For example, afiberglass mat can include glass fibers in the form of an openstructure. The outer surfaces of the fiberglass mat are used todetermine the perimeter volume. The volume occupied by only the glassfibers within the fiberglass mat may be substantially less than theperimeter volume.

The term “principal surfaces,” with respect to a roofing article orproduct, is intended to mean a pair of opposite surfaces of such roofingarticle or product, wherein one of the surfaces lies or would liefarther from a structure to which the roofing article or product isinstalled or intended to be installed, and the other surface of suchroofing article or article lies or would lie closer to a structure towhich the roofing article or article is installed or intended to beinstalled. When installed, the principal surface farther from thestructure may be directly exposed to an outdoor environment, and theother principal surface may contact the structure or a different roofingarticle or product that lies between the other principal surface and thestructure.

The term “recycled roofing material” is intended to mean a material thatincludes at least some roofing article content that is or will become acoating or other component within a roofing product. Recycled roofingmaterial may include at least some material that is not recycled.

The term “roofing article” is intended to mean a roofing product(recently manufactured or used) or a byproduct of a roofingmanufacturing process that can be recycled and used to make a newlymanufactured roofing product.

The term “roofing product” is intended to mean a final product or anintermediate product of a roofing manufacturing process.

As used herein, the terms “comprises,” “comprising,” “includes,”“including,” “has,” “having” or any other variation thereof, areintended to cover a non-exclusive inclusion. For example, a method,article, or apparatus that comprises a list of features is notnecessarily limited only to those features but may include otherfeatures not expressly listed or inherent to such method, article, orapparatus. Further, unless expressly stated to the contrary, “or” refersto an inclusive-or and not to an exclusive-or. For example, a conditionA or B is satisfied by any one of the following: A is true (or present)and B is false (or not present), A is false (or not present) and B istrue (or present), and both A and B are true (or present).

Also, the use of “a” or “an” is employed to describe elements andcomponents described herein. This is done merely for convenience and togive a general sense of the scope of the invention. This descriptionshould be read to include one or at least one and the singular alsoincludes the plural, or vice versa, unless it is clear that it is meantotherwise. For example, when a single item is described herein, morethan one item may be used in place of a single item. Similarly, wheremore than one item is described herein, a single item may be substitutedfor that more than one item.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. The materials, methods, andexamples are illustrative only and not intended to be limiting. To theextent not described herein, many details regarding specific materialsand processing acts are conventional and may be found in textbooks andother sources within the roofing product arts and correspondingmanufacturing arts.

The inventors have discovered that one or more particular coatings of aroofing product can include a recycled roofing material having arecycled roofing content relatively lower, such as less than 40 weight%, where an application for such roofing product allows for some, butnot too much recycled roofing content. For example, one or more coatingsof the roofing product can include a recycled roofing material having arelatively lower recycled roofing content, where the recycled content isused as an additive to modify some aspect or property of the roofingproduct. In another example, one or more coatings of the roofing productcan include a recycled roofing material having a relatively lowerrecycled roofing content, where post-industrial waste is employed and arecycled waste stream resulting therefrom is not sufficient to provide arelatively higher recycled roofing content. In another embodiment, therecycled roofing content can be no greater than 30 weight %, in afurther embodiment, the recycled roofing content can be no greater than25 weight %, and in still another embodiment, the recycled roofingcontent can be no greater than 20 weight %.

In one embodiment, a coating can include a high content of recycledroofing material. Such a coating may be relatively stiff. An adjacentcoating may include a lower recycled roofing material or no recycledroofing material, may include a higher additive chemicals content (e.g.,a higher plasticizer content), may be less oxidized, may have anothersuitable difference, or any combination thereof to compensate for therelatively stiffer coating. In a particular embodiment, a roofingproduct can include complementary pairs of coatings that synergisticallyprovide for more desirable properties, lower manufacturing costs,provide another benefit or any combination thereof.

FIG. 1 includes a process flow of an exemplary, non-limiting method offorming a roofing product in accordance with an embodiment. At block102, a base material is provided. For example, the base material caninclude a portion of a roll. The base material can include a ceramicbase material, such as fiberglass, alumina, silica or another vitreousor non-vitreous ceramic base material. In one embodiment, the basematerial includes a fiberglass mat. In another embodiment, the basematerial can include polyester, wood, paper cellulose fiber, or anothernon-ceramic material. The base material has a length, a width, and athickness. The base material also has principal surfaces that areopposite one another, such as principal surfaces whose areas are definedby the length and width on opposite sides of the base material.

The base material can have an open structure that allows a bituminousmaterial or other material to flow within and partially or completelyfill the open structure. The open structure can be in the form of pores,channels, interstitial openings within a matrix, another suitable void,or any combination thereof. The open structure can be characterized asthe volume of the base material that is not occupied by the particularmaterial (e.g., paper, glass fibers, etc.) and may be expressed as a matweight. In an embodiment, the mat weight can be at least approximately25 g/m² (0.5 lb/100 ft²), at least approximately 40 g/m² (0.8 lb/100ft²), or at least approximately 60 g/m² (1.2 lb/100 ft²). In anotherembodiment, the mat weight can be no greater than approximately 200 g/m²(4.0 lb/100 ft²), no greater than approximately 170 g/m² (3.5 lb/100ft²), or no greater than approximately 130 g/m² (2.7 lb/100 ft²). In aparticular embodiment, the mat weight can be in a range of approximately60 g/m² (1.3 lb/100 ft²) to approximately 120 g/m² (2.5 lb/100 ft²).When a ceramic base material is used, the ceramic base material caninclude an oxide (e.g., silica, alumina, ceria, zirconia, or the like),a nitride (e.g., aluminum nitride, silicon nitride, or the like), acarbide (e.g., tungsten carbide, silicon carbide, or the like), or anycombination thereof. In another embodiment, a mat can include polyester,wood, paper cellulose fiber or another non-ceramic material.

The method includes, at block 104, preparing bituminous materials to beused as portions of the roofing product, such as a coating, a materialto fill the open structure of the base material, another portion of theroofing product, or any combination thereof. The bituminous materialsinclude asphalt, roofing articles, or both, and may include a filler,additive chemicals, another suitable component, or any combinationthereof. The actual composition of the bituminous material may depend onwhere in the roofing product the bituminous material will be used. Threetypes of bituminous materials are described below: (i) virgin asphalt orfilled virgin asphalt mixture (after adding filler and potentiallyadditive chemicals); (ii) bituminous material having at least 40 weight% recycled roofing material content (“high recycled content bituminousmaterial”); and (iii) bituminous material having less than 40 weight %recycled roofing material content, a relatively higher additivechemicals content as compared to the recycled roofing material, or anycombination thereof (“low recycled content bituminous material”). Asused in this specification, low recycled content bituminous material mayor may not include a recycled roofing article. When the low recycledcontent bituminous material has substantially no recycled roofingarticle, such low recycled content bituminous material has a recycledroofing content of zero.

In one embodiment, each of the high recycled content bituminous materialand the low recycled content bituminous material can include virginasphalt or filled virgin asphalt mixture. Virgin asphalt and filledvirgin asphalt mixture includes asphalt that has not been previouslyincorporated into a roofing product and is processed to achieve desiredproperties. In an embodiment, asphalt, as received, can be oxidized toreduce the amount of volatile chemicals, partially polymerize a compoundwithin the asphalt, or a combination thereof. The process can be used toincrease the softening point of the asphalt to over approximately 90° C.(approximately 200° F.) or a penetration distance (100 g at 25° C., ASTMD5) of less than 18 to 22 dmm. In a particular embodiment, asphalt isoxidized by flowing pressurized air into a tank of asphalt heated toapproximately 230° C. (approximately 450° F.). For the purposes of thisspecification, asphalt as received or after the oxidation process, butbefore adding solids or chemicals, is referred to herein as virginasphalt and can be used to form filled virgin asphalt mixture.

As compared to one another, the high recycled content bituminousmaterial can have lower virgin asphalt content as compared to thebituminous base material and the low recycled content bituminousmaterial. For example, the low recycled content bituminous material mayhave a virgin asphalt content of at least approximately 20 weight %, 30weight %, or 50 weight %, and in another embodiment, the virgin asphaltcontent may be no greater than approximately 95 weight %, 90 weight %,or 80 weight %. The high recycled content bituminous material may haveno virgin asphalt or may have virgin asphalt content of at leastapproximately 5 weight %, 10 weight %, 15 weight %, or 20 weight %, andin another embodiment, the virgin asphalt content in the high contentroofing material may be no greater than approximately 80 weight %, 60weight %, or 40 weight %.

As stated, each of the low recycled content bituminous material and thehigh recycled content bituminous material can also include a filler. Afiller allows a relatively less expensive material to displacerelatively more expensive asphalt within a roofing product. The fillercan include relatively inert solid particles. More particularly, thefiller can include limestone particles, sand, talc, clay, coal fines,gypsum, calcite, another similar material, or any combination thereof.

For a bituminous material that is used to fill the open structure of thebase material, the selection of filler material may depend on thecomposition of base material within the roofing product. When the basematerial is not a ceramic base material (e.g., wood, paper, polyester),the filler material may include any filler previously described. For aceramic base material, the material used for filler may depend on theparticular material within the ceramic base material and whether theceramic base material provides a principal support within the roofingproduct. For example, the roofing product can include a laminatedroofing product, as described in further detail later in thisspecification. Such a laminated roofing product can include a pluralityof sheets laminated together, where each sheet includes a ceramic basematerial. In a particular embodiment, the ceramic base material in aparticular sheet can provide principal support for the roofing product,whereas the ceramic base material in another particular sheet does notprovide principal support for the roofing product.

A filler that will not significantly scratch or otherwise damage theceramic base material that provides principal support for the roofingproduct can be used to reduce or prevent failure of the roofing productdue to tearing of the ceramic base material. For example, limestoneparticles, talc, clay, non-abrasive coal fines, gypsum, calcite, anothersimilar material, or any combination thereof can be included within afiller used with a fiberglass mat providing principal support for theroofing product. In another example, limestone particles, sand, othersimilar abrasive filler materials, or any combination thereof, can beused as a filler for a fiberglass mat or other ceramic base materialthat does not provide principal support for the roofing product, or whenthe ceramic base material that provides principal support for theroofing product includes a harder material, such as alumina.

In another embodiment, the filler used with the bituminous materialsprepared at block 104 can include roofing granules or other abrasiveparticles, such as sand or other abrasive particles. Roofing granulescan include materials that are harder than glass and may scratch glassfibers within a fiberglass mat. Nonetheless, a relatively small amountof roofing granules or other abrasive particles may be used within aperimeter volume of a ceramic base material, such as a fiberglass mat,without causing a substantial failure of a roofing product having aceramic base material, even when the ceramic base material providesprincipal support for the roofing product. For instance, a bituminousmaterial having no greater than 5 weight % roofing granules (or otherabrasive particles) or no greater than 3 weight % roofing granules (orother abrasive particles) can be used. In another embodiment, thebituminous material has no greater than 1 weight % roofing granules (orother abrasive particles), and in a further embodiment, the bituminousmaterial is substantially free of roofing granules (or other abrasiveparticles). More details regarding roofing granules are described infurther detail within this specification.

In a shingle embodiment, the bituminous materials prepared at block 104can include at least approximately 45 weight % of filler, at leastapproximately 50 weight % of filler, or at least approximately 55 weight% of filler. In another shingle embodiment, the bituminous material mayinclude no greater than approximately 80 weight % of filler, no greaterthan approximately 75 weight % of filler, or no greater thanapproximately 70 weight % of filler. In a membrane embodiment, thebituminous material may include substantially no filler or may includeat least approximately 5 weight % of filler, or at least approximately10 weight % of filler. In another membrane embodiment, the bituminousmaterial may include no greater than approximately 60 weight % offiller, no greater than approximately 50 weight % of filler, or nogreater than approximately 40 weight % of filler. In a furtherembodiment, the bituminous material can include a higher or a lowerfiller content than the weight percents recited.

Additive chemicals that can be used with the bituminous material includea process oil, a plasticizer, a polymer modifier, another suitablecompound, or any combination thereof. The process oil can include anapthenic oil, an aliphatic oil, or an aromatic oil, another suitableoil, or any combination thereof. Another exemplary compound can includestyrene-butadiene-styrene, styrene-ethylene-butylene-styrene,styrene-isoprene-styrene, acrylonitrile-butadiene-styrene, atacticpolypropylene, isotactic polypropylene, high density polyethylene,ethylene-polypropylene copolymer, another suitable plasticizer orpolymeric compound, or any combination thereof. A thermoplastic olefincan be formed using a metallocine catalyst and include a block copolymerpolypropylene, a polyethylene-propylene rubber, or another suitablematerial. Typically, the additive chemicals are in the form of solids orliquids at room temperature; however, the additive chemicals do notinclude asphalt, fillers, or roofing granules. For simplicity, theadditive chemicals are referred to herein in the plural even if only asingle chemical is used.

In an embodiment, the high recycled content and low recycled contentbituminous materials may include substantially none of the foregoingadditive chemicals, at least approximately 5 weight % of additivechemicals, or at least approximately 10 weight % of additive chemicals.In another embodiment, the bituminous materials may include no greaterthan approximately 40 weight % of additive chemicals, no greater thanapproximately 30 weight % of additive chemicals, or no greater thanapproximately 25 weight % of additive chemicals. In a furtherembodiment, the bituminous materials can include a higher or a loweradditive chemical content than the weight percents recited. Whencomparing the high recycled content bituminous material and the lowrecycled content bituminous material, the low recycled contentbituminous material may have a higher additive chemicals content. Thehigher additive chemicals content can help to improve its impactresistance. In a particular embodiment, the low recycled contentbituminous material may have one or more plasticizers that are notpresent or are present at a lower content within the high recycledcontent bituminous material.

In a particular embodiment, recycled roofing material, as describedbelow, may be used in the bituminous material prepared at block 104,such as the high recycled content bituminous material and the lowrecycled content bituminous material. When the base material of theroofing product is not a ceramic base material (e.g., wood, paper,polyester, etc.), or in a ceramic base material that does not provideprincipal support for the roofing product, the selection of thecomponents and content of those components within the recycled roofingmaterial is more flexible and may include any recycled roofing materialas previously described with respect to the high recycled contentbituminous material or the low recycled content bituminous material.

However, for a ceramic base material that provides principal support forthe roofing product, the components and content of the components withinthe recycled roofing material, if any recycled roofing material is usedwithin the bituminous material used to fill the open structure of thebase material, may depend on the particular material within the ceramicbase material. In a particular embodiment, when the ceramic basematerial provides principal support for the roofing product and includesa fiberglass mat, the particles within the recycled roofing material caninclude limestone particles or any other material that will not scratchor abrade the fiberglass, and when the ceramic base material includesalumina, the filler particles can include limestone particles, sand, orany other material that will not scratch or abrade the alumina. Thussimilar to the description with respect to filler, roofing granules maybe used in greater quantities for an alumina base material than afiberglass base material.

In a particular embodiment, the recycled roofing material used in thelow recycled content and high recycled content bituminous materials caninclude recycled roofing articles (e.g., membranes, shingles, roofer'sfelt, etc.), other materials recovered when removing roofing articlesfrom a structure, virgin asphalt or filled virgin asphalt mixture, anadditive chemical, another component, or any combination thereof.Recycled roofing articles can include post-industrial roofing articles,pre-consumer roofing articles, post-consumer roofing articles, or anycombination thereof. Post-industrial roofing articles can includepartially or completely manufactured roofing articles that remain withinthe possession of the manufacturer. An example of a recycled roofingarticle can include a post-industrial roofing article that does not meeta product specification. Post-consumer roofing articles can includeroofing articles that have been installed on a structure owned orcontrolled by a consumer, such as a homeowner or a business.Pre-consumer roofing articles are completely manufactured roofingarticles outside the possession of the manufacturer and before theroofing articles are installed. An example of pre-consumer roofingarticles can include a bundle of shingles that is damaged by a shippingcompany or a roofing contractor during shipping or handling, or obsoleteproducts, such as roofing articles with outdated colors or designs, orexpired products (e.g., a product that should not be installed on a roofdue to age of the product).

Roofing articles that are being recycled vary greatly with respect totime and exposure to different environmental conditions. Some roofingarticles may be recently scrapped, such as post-industrial roofingarticles that do not meet product specifications, and therefore, cannotbe sold as product. Post-industrial roofing articles can also includecut-outs from the shaping of the shingles during manufacturing (e.g.,the cut-outs may correspond to slots that were formed in a finishedthree-tab shingle). Other roofing articles may be pre-consumer roofingarticles that may have been stored at a warehouse or other locations formonths. Roofing articles may be post-consumer roofing articles that mayhave been installed on different structures for years that experiencedifferent environmental conditions. For example, roofing articlesinstalled on a structure exposed to more sun will have received moreultraviolet radiation than roofing articles installed on a differentstructure exposed to less sun. As time elapses and effective exposure toultraviolet radiation increases, the composition of materials within theroofing articles can change. For example, volatile chemicals orplasticizers may be driven off or degraded, and further polymerizationof an asphalt material may occur.

Particular chemicals or compounds can be used with recycled roofingmaterial to replace, replenish, or otherwise provide the same or othercompounds that have been volatilized or have become degraded. Suchcompounds can include a process oil, a plasticizer, a polymer modifier,another suitable compound, or any combination thereof. As compared tothe bituminous material using virgin asphalt as a sole bituminoussource, the additive chemicals may make up a larger fraction of thestarting materials when preparing the bituminous material that includesrecycled roofing articles. In one embodiment, virgin asphalt or filledvirgin asphalt mixture can be used in recycled roofing material withrecycled roofing articles, and in another embodiment, virgin asphalt,filled virgin asphalt mixture, or both are not used. If the highrecycled content bituminous material, the low recycled contentbituminous material, or both, are to be relatively more flexible or lessstiff, a relatively higher additive chemical content may be used.Conversely, if the high recycled content bituminous material, the lowrecycled content bituminous material, or both, are to be relatively lessflexible or stiffer, a relatively lower additive chemical content may beused.

With respect to recycled roofing articles, in an embodiment, therecycled roofing article content within recycled roofing material may beat least approximately 5 weight %, 10 weight %, 15 weight %, or 20weight %, and in another embodiment, the recycled roofing articlecontent may be no greater than approximately 95 weight %, 90 weight %,or 80 weight %. The high recycled content bituminous material has agreater recycled roofing article content than the low recycled contentbituminous material. The low recycled content bituminous material may ormay not include recycled roofing articles (i.e., 0 weight % recycledroofing articles).

In another particular embodiment, recycled roofing material used in thelow recycled content and high recycled content bituminous materials mayinclude wood, paper, fiberglass, polyester, or another material that mayhave been part of a base material used in shingles or a membrane of aroofing article. Additionally, or alternatively, the recycled roofingmaterial may include one or more metals from nails, flashing, or frommetal fragments generated when making the recycled material (e.g.,fragments from steel balls or exposed surfaces within a mixing orgrinding apparatus). These metals can include iron, aluminum, copper,chromium, nickel, or the like, in elemental form (i.e., the metalelement by itself and not part of a compound) or as part of an alloy. Inan embodiment, the recycled roofing material may be substantially freeof the wood, paper, fiberglass, polyester other base material, andmetals content. In another embodiment, the wood, paper, fiberglass,polyester, another base material, or metals content within the recycledroofing material may be at least approximately 5 weight %, 10 weight %,or 15 weight %, and in another embodiment, the wood, paper, fiberglass,polyester, other base material or metals content within the recycledroofing material may be no greater than approximately 30 weight %, 25weight %, or 20 weight %.

Many different materials have been described for use within the recycledroofing material. Any detectible amount of a residual material fromroofing articles, a roof, or equipment used to process recycled roofingmaterial can provide proof that recycled roofing material is presentwithin a roofing product. These residual material can include theroofing granules or sand, a roofing article base material (e.g.,fiberglass or polyester mat, wood, paper, or the like), a roofingarticle coating (e.g., an acrylic material), a metal from roofing nails,wood from the roof decking (e.g., plywood), parts of a gutter,downspout, or screen, a material from grinding media (e.g., ceramic orsteel balls) or a drum used in breaking down the roofing articles whenprocessing the recycled roofing material, or any combination thereof.Thus, in a non-limiting embodiment, even 0.1 weight % of any of theresidual materials within a particular coating or other component of aroofing product indicates that recycled roofing material is present.

In an illustrative embodiment, the presence of recycled roofing materialcan be detected by determining the level of acid-insoluble solidsdisposed within a coating of a roofing product or a portion of suchcoating. Roofing granules and parting agents, such as sand, talc, or thelike, if present along the principal surfaces of the roofing product,are removed from the exposed surfaces of the roofing product. Theremaining coating of the roofing product or portion thereof is placed inan appropriate solvent to extract the bituminous material. One or moresolvents can be used, and the extraction can be performed as a singlewash or a series of washes. In a particular embodiment, a Soxhlet methodcan be used. After the bituminous material is removed, solids remain andinclude a mat (e.g., fiberglass, polyester, cellulose, etc.), filler,and solids from the recycled roofing material. If the particular coatingor portion thereof includes an embedded mat (e.g., fiberglass,polyester, cellulose, etc.) that is part of the base structure (that is,not residual pieces of a mat within the recycled roofing material), themat can be removed at this time to form remaining solids.

The remaining solids can then be further processed by disposing thesolids in an acid. Acid washing can be used to determine the presenceand amount of collateral abrasive content in nonabrasive fillers used inroofing materials. More particularly, limestone is primarily calciumcarbonate, and calcium carbonate can be dissolved in an HCl solution.Other materials, such as silica, roofing granules, and metals and metalsalloys, do not significantly dissolve in an HCl solution. Thus, bywashing the solids in the HCl solution, calcium carbonate from thelimestone is dissolved, and acid-insoluble solids remain. Theacid-insoluble solids can then be vacuum filtered onto a tared filterpaper. After drying and removing the filter paper, the acid-insolublesolids are typically silica, roofing granules, and metals and metalsalloys. When the filler principally includes a material other thancalcium carbonate, the selection of the acid can be changed to removethe other material while at least some other solids remain.

For a conventional roofing product having limestone filler, the amountof acid-insoluble solids is relatively low because a small amount of thelimestone may include silica or another similar material. A particularconventional roofing product that does not include any recycled roofingmaterial may have an acid-insoluble solids content of approximately 1.6%of the remaining solids. Thus, a conventional roofing product withoutany recycled roofing material has less than 2% of the remaining solids.

Clearly, a roofing product including recycled roofing material has asignificantly higher acid-insoluble solids content than a conventionalroofing product without any recycled roofing material. The recycledroofing material includes roofing granules, many of which are silicates,sand, residual fiberglass mat, metals or metal alloys from a grindingdrum or grinding media, or potentially other sources of acid-insolublematerials that may not be present in a conventional roofing product, orif present, at significantly lower levels. Therefore, a coating of aroofing product or portion of such coating including recycled roofingmaterial can have at least 2% acid-insoluble solids (as a percentage ofthe remaining solids), and in a particular embodiment, at least 3%acid-insoluble solids.

In a particular embodiment in which the coating or portion of suchcoating includes approximately 3 weight % recycled roofing content, theamount of acid-insoluble solids may be approximately 4.0% of theremaining solids. In another particular embodiment in which the coatingor portion of such coating includes approximately 6 weight % recycledroofing content, the amount of acid-insoluble solids may beapproximately 5.0% of the remaining solids. In still another particularembodiment in which the coating or portion of such coating includesapproximately 12 weight % recycled roofing content, the amount ofacid-insoluble solids may be approximately 8.4% of the remaining solids.Thus, the content of acid-insoluble solids provides a good indiciaregarding the presence and level of recycle roofing material within acoating of a roofing product or portion of such coating.

Particle size distribution may be an additional indicator that recycledroofing articles are present within a roofing product. A particle sizedistribution can have characteristic particle size. In a particularembodiment, the characteristic particle size can be an averaged particlesize, such as an average, a geometric mean, or a median. Alternatively,the characteristic particle size may be expressed as a percentile. Forexample, the characteristic particle size may be the particle size atthe 5^(th) percentile, 95^(th) percentile, or other percentile value.For a 95^(th) percentile value, the characteristic particle size wouldmean that 95 percent all particles are a particular particle size orsmaller. In still another embodiment, the characteristic particle sizecan be the largest particle size of all the particles present. Inanother embodiment, the characteristic particle size may be determinedusing a different criterion.

In a particular embodiment, the characteristic particle size within therecycled roofing material is smaller than the characteristic particlesize used within conventional asphalt shingles. In a particularembodiment, the characteristic particle size within the recycled roofingmaterial is no more than 70%, 50%, or 30% of the characteristic particlesize used within conventional asphalt shingles.

FIG. 2 includes an illustration of a particle size distribution ofconventional limestone filler within an asphalt coating as measured by aCoulter counter, and FIG. 3 includes an illustration of a particle sizedistribution of recycled roofing material. The recycled roofing materialcan be prepared using a Union Process Attritor Model 1-S, approximately9 mm (⅜ inch) grinding media and a rotational speed of between 100 to650 rotations per minute.

In this particular embodiment, the characteristic particle size can be amedian particle size or the size at the 5^(th) or 95^(th) percentile.Referring to FIG. 2, for the conventional limestone filler, the medianparticle size is 44 microns with 5^(th) and 95^(th) percentiles at 1.4and 260 microns, respectively. Referring to FIG. 3, for the recycledroofing material, the median particle size is 14 microns, about ⅓ themedian particle size of the conventional limestone filler, and the5^(th) and 95^(th) percentiles at 1.8 and 81 microns, respectively.Thus, the recycled roofing material can have a tighter distribution ofparticle size as compared to limestone filler used in conventionalasphalt shingles. In another embodiment, a different apparatus, adifferent size of grinding media, a different rotational speed, or anycombination thereof can be used to prepare the recycled roofingmaterial. Thus, a smaller median particle size and an even tighterdistribution of particle sizes may be achieved.

In another embodiment, the particle size distribution of particles in acoating can include a plurality of modes, wherein a particular mode isindicative of recycled material, another particular mode is indicativeof a conventional filler, a further particular mode is indicative offilled virgin asphalt mixture or other fresh content, or any combinationthereof. For example, one of the modes may correspond to a particle sizedistribution as illustrated in FIG. 3. In still another embodiment, anysignificant deviation from the particle size distribution in FIG. 2 mayalso be indicative of recycled roofing material being present.

The process used in preparing the recycled roofing material may becarried out as a batch or continuous operation. The processing apparatusmay include steel balls, ceramic grinding media, or other items that mayhelp to break up the recycled roofing articles into smaller pieces. In aparticular embodiment, virgin asphalt or filled virgin asphalt mixturecan be heated above its softening point. Additive chemicals can becombined with the virgin asphalt or filled virgin asphalt mixture beforeor after the virgin asphalt is above its softening point. Recycledroofing articles can be combined with the heated virgin asphalt orfilled virgin asphalt mix, and potentially additive chemicals. If neededor desired additional filler particles can be added to achieve a desiredparticle content for the recycled roofing material. In anotherparticular embodiment, all components for the recycled roofing materialcan be combined within the apparatus before or after heating. In stillanother particular embodiment, a different order of adding thecomponents may be used. After reading this specification, skilledartisans will appreciate that the order in which components are firstcombined can be tailored to the particular needs or desires for aparticular apparatus and application. The recycled roofing material canbe in a softened state and optionally may be filtered or magneticallyseparated during or after preparing the recycled roofing material toremove roofing nails or other undesired items.

Recycled roofing articles can be ground within a media mixer. In aparticular embodiment, the media mixer is an attritor that includes amixing vessel, mixing media, and an agitator. The mixing vessel, mixingmedia, agitator, and virgin asphalt or filled virgin asphalt mixture areheated to approximately 210° C. (approximately 400° F.), with theagitator rotating at approximately 100 revolutions per minute (rpm) forapproximately 5 minutes. After mixing media and virgin asphalt or filledvirgin asphalt mixture have been mixed, recycled roofing articles can beadded.

Before adding the recycled roofing articles, the amount of recycledroofing articles to be added can be determined in order to achieve adesired amount of filler (solids) that is to be present within themixture. The roofing articles can include parts of fiberglass mats,roofing granules, sand or talc (from parting agents), limestone, or anycombination thereof. If the mixture is to include approximately 50weight % filler, the mixture can include approximately 40 weight %virgin asphalt or filled virgin asphalt mixture and approximately 60weight % recycled roofing articles. As the desired amount of filler orcomposition of the recycled roofing articles within the mixture changes,the relative amounts of virgin asphalt and recycled roofing articles canlikewise change.

The recycled roofing articles can be added all at once into the vesselor may be added in segments. When the mixture includes approximately 60weight % recycled roofing articles, the recycled roofing articles can beadded in two (halves) or three (thirds) different stages, with eachstage having approximately the same amount of recycle roofing articles.During each stage, the agitator can be stopped and the desired amount ofrecycled roofing articles can slowly be added. The mixture can be mixedwith the agitator rotating at approximately 100 rpm for approximately 1minute, and then the rotational speed of the agitator can be increasedto approximately 350 rpm for approximately 1 minute. The process can beiterated for the remainder of the stages until all of the recycledroofing articles are added.

After all of the recycled roofing articles have been mixed as describedabove, the resulting mixture can be mixed with the agitator at arotational speed of approximately 350 rpm for approximately 20 minutesto form a ground mixture. Throughout the process, the temperaturesetpoint can remain at approximately 210° C. (approximately 400° C.).The ground mixture can then be drained or otherwise removed from thevessel. The ground mixture may have the particle size distribution asillustrated in FIG. 3. While the process has been described with respectto an attritor, skilled artisans will appreciate that other equipmentand processes can be used to produce the ground mixture. For example, arotating ball mill is another media mixer that can be used in formingthe ground mixture.

Table 1 includes properties of three different batches of the groundmixture. In Table 1, the softening point is determined using ASTMD-36-06, the viscosity is determined using ASTM D-4402-06, thepenetration is determined using ASTM D-5 as described in ASTM D-449-03,and the stain test is determined using ASTM D-2746-07. As used in thetables in this specification, “Total Solids” refers to solids contentafter asphalt is removed.

TABLE 1 Target Grind 1 Grind 2 Grind 3 Softening Point (° F.) 134 136136 Viscosity (cps) @ 300° F. 875 1050 1075 325° F. 500 575 588 350° F.250 350 363 Penetration (dmm)  77° F. 38 35 37 115° F. 176 170 162Remaining Solids (wt %) 50% 45.7 47.0 47.7 Acid-Insoluble Solids 55%50.8 50.0 51.1 (% of Remaining Solids) Stain ( 1/64s of an inch) 11.5 87.5

Information in the Table 1 can be expressed in metric units. Thesoftening point of Grinds 1, 2, and 3 are approximately 57° C., 58° C.,and 58° C., respectively. The temperatures for determining theviscosities are approximately 149° C., 163° C., and 177° C., and thetemperatures for determining the penetrations are approximately 25° C.and 46° C. The stain distance of Grinds 1, 2, and 3 are approximately4.6 mm, 3.2 mm, and 3.0 mm, respectively.

In other embodiments, different levels of total solids content can bedifferent for the ground mixture. The amount of virgin asphalt added maybe adjusted to achieve a desired total solids content, viscosity, orboth.

In an embodiment, the ground mixture can be used as a recycled roofingmaterial. In another embodiment, another material may be added to reducethe recycled content for the recycled roofing material. A filled virginasphalt mixture can include virgin asphalt, limestone or other fillers,and potentially additive chemicals. A combination of the filled virginasphalt mixture and the ground mixture can be combined to form therecycled roofing material. In a particular embodiment, the recycledroofing material can include approximately 5 weight % of the groundmixture with the remainder substantially the filled virgin asphalt mix(recycled roofing material is approximately 3% recycled roofingcontent). In another embodiment, the recycled roofing material caninclude approximately 10 weight % of the ground mixture with theremainder substantially the filled virgin asphalt mixture (recycledroofing material is approximately 6% recycled roofing content). In yetanother embodiment, the recycled roofing material can includeapproximately 20 weight % of the ground mixture with the remaindersubstantially the filled virgin asphalt mixture (recycled roofingmaterial is approximately 12% recycled roofing content). In still otherembodiment, part or all of the virgin asphalt can be replaced bystyrene-butadiene-styrene (SBS) or another polymer. In a particularembodiment, 10 weight % SBS can be used.

Table 2 below includes data for a roofing product that includes afiberglass mat that is filled with filled virgin asphalt mixture(control), 10 weight % ground mixture with the remainder filled virginasphalt mixture (10% mixture), and 20 weight % ground mixture with theremainder filled virgin asphalt mixture (20% mixture). Tests asdescribed with respect to Table 1 can be used to obtain the data inTable 2. In addition, the tear test can be determined using ASTM D-1922as modified in D-228-08.

TABLE 2 10% 20% Target Control mixture mixture Softening Point (° F.)205-225 226 212 197 Viscosity (cps) 350° F. 4188 3000 1800 375° F.1500-3000 2000 1580 988 400° F. 1138 875 625 Penetration (dmm)  77° F. 711 13 115° F. 15 18 25 Remaining Solids (wt %) 50% 55.5 55.2 53.3Acid-Insoluble Solids 1.63 6.62 11.01 (% of Remaining Solids) % recycleadded based on 10.3 19.4 Acid-Insoluble Solids Stain ( 1/64s of an inch)5.5 6.5 6.3 Tear Test (g) CD 1700 1800 1400 1300 MD 1300 1100 1000

Information in the Table 2 can be expressed in metric units. Thesoftening point of Control, 10% mixture, and 20% mixture areapproximately 108° C., 100° C., and 92° C., respectively. Thetemperatures for determining the viscosities are approximately 177° C.,191° C., and 204° C., and the temperatures for determining thepenetrations are approximately 25° C. and 46° C. The stain distance ofControl, 10% mixture, and 20% mixture are approximately 2.2 mm, 2.6 mm,and 2.5 mm, respectively.

The target for total solids is 50 weight %. The control, 10% mixture,and the 20% mixture have a solids content of about 53 to 56 weight %solids. Clearly, the acid-insoluble solids content increases with ahigher amount of ground mixture. Thus, the control has about 1.6%acid-insoluble solids, the 10% mixture has approximately 6.6%acid-insoluble solids, and the 20% mixture has approximately 11%acid-insoluble solids. Solely by using the acid soluble solids andknowing the composition of the filled virgin asphalt mixture and theground mixture within the recycled roofing material, the ground mixturecontent within the recycled roofing material can be calculated (“%recycle added based on Acid-Insoluble Solids” in Table 2). The 10%mixture is calculated to be approximately 10 weight % ground mixture,and the 20% mixture is calculated to be approximately 19 weight % groundmixture. Thus, acid insoluble content can be used not only to determinethe presence or absence of recycled roofing material, but it can also beused to estimate the amount of ground mixture within the recycledroofing material.

Viscosity decreases and penetration distance increases with increasingthe ground mixture content. Stain distance is not significantly affectedby the increased ground mixture content.

Particularly noteworthy is the tear strength as determined by the teartest. The tear test is performed in the machine direction (MD), which issubstantially parallel to the direction in which the roofing product isprincipally moved during manufacturing, and the cross direction (CD),which is perpendicular to the machine direction. The tear strength inboth directions decreases with an increasing ground mixture content.With respect to CD, the tear strength of the control roofing product isapproximately 1800 grams, which is above the specification of 1700grams. However, the tear strength decreases to 1400 and 1300 grams forthe 10% mixture and the 20% mixture, respectively. The solids fromrecycled roofing articles can include abrasive particles that arebelieved to fracture or scratch the fiberglass mat and lead to prematuretearing in the CD and MD at levels below that seen with the control.

Table 3 below include data for a roofing product similar to the roofingproduct in Table 2, except that the fiberglass mat is replaced with apolyester mat and the filled virgin asphalt mixture includes 10 weight %of SBS polymer. The tear test for the roofing products in Table 3 wasperformed as a notched tear in order to initiate tearing. This tear testcan be determined using ASTM D-4073, as modified in ASTM D-5147-07b.

TABLE 3 10% 20% Target Control mixture mixture Softening Point (° F.)260-290 256 255 247 Viscosity @ 350° F. 4375 4375 3625 (cps) 375° F.2800-4200 3000 2350 1825 400° F. 2300 1600 1300 Penetration (dmm)  77°F. 40-50 39 29 30 115° F. 78 64 67 Remaining Solids (wt %) 30.0% 27.4%31.2% 33.6% Acid-Insoluble Solids 1.61 12.1 20.8 (% of Remaining Solids)% recycle added based on 13.0% 25.7% acid-insoluble solids Stain ( 1/64sof an inch) 3 3 4 Tear Test (lbf) CD 55 75 70 70 MD 55 120 110 120

Information in the Table 3 can be expressed in metric units. Thesoftening point of Control, 10% mixture, and 20% mixture areapproximately 124° C., 124° C., and 119° C., respectively. Thetemperatures for determining the viscosities are approximately 177° C.,191° C., and 204° C., and the temperatures for determining thepenetrations are approximately 25° C. and 46° C. The stain distance ofControl, 10% mixture, and 20% mixture are approximately 1.2 mm, 1.2 mm,and 1.6 mm, respectively.

Many of the trends seen with the roofing products in Table 3 are similarto those seen with the roofing products in Table 2. However, the trendseen with the tear test for the roofing products in Table 3 differs fromtrend seen with the tear test for the roofing products in Table 2. Thetear strength of the roofing products with recycled roofing material issimilar to the tear strength of the roofing product without any recycledroofing material. Therefore, abrasive particles, which can scratchglass, do not have a significantly adverse affect on the roofingproducts that include a polyester mat for a base material.

In summary, with respect to preparation of the recycled roofingmaterial, many different materials, content of those materials,particular actions in preparing the recycled roofing material, or anycombination thereof are disclosed. After reading this specification,skilled artisans will appreciate that preparing the recycled roofingmaterial can be modified to include other materials, content of thosematerials, particular actions in preparing the recycled material, or anycombination thereof to meet the needs or desires for a particularapplications.

Preparation of the bituminous material at block 104 can includecombining and heating the components for the bituminous material (e.g.,virgin asphalt, filled virgin asphalt mixture, recycled roofingmaterial, a filler, an additive chemical, another component, or anycombination thereof) to a temperature above the softening point of theasphalt. The components can be first combined and then heated, or theasphalt can be heated, and then the other components can be added to thesoftened asphalt. After reading this specification, skilled artisansappreciate that the order of heating, combining or otherwise introducingcomponents in forming the bituminous material can be chosen to meet theneeds or desires for a particular application. The bituminous materialcan be prepared in a conventional or proprietary apparatus used inpreparing asphalt for use in roofing products.

When a bituminous material includes recycled roofing material, one ormore operations may be different as compared to when a bituminousmaterial does not include any recycled roofing material. Any of thecomponents for the recycled roofing material can be initially processedbefore such component is used. For example, recycled roofing articlesmay have roofing nails or other undesired items removed. Recycledroofing articles may or may not be cut or shredded to reduce theindividual sizes of the roofing articles. In one particular embodiment,recycled roofing articles are reduced in size to dimensions of about 10cm×15 cm (4″×6″) prior to adding to the media mixer. In otherembodiments, the recycled roofing articles may be larger or smaller insize. The virgin asphalt, filled virgin asphalt mixture, or chemicalsmay be preheated. Other initial processing may be performed as needed ordesired.

At block 106, the method includes filling the open structure of the basematerial provided at block 102. The open structure of the base materialmay be substantially completely filled with low recycled content or highrecycled content bituminous material prepared at block 104, depending onthe material of the base material, whether the base material providesprincipal support for the roofing product, or a combination thereof, asexplained previously. The outermost portions of the base material withinthe saturated base material may or may not be exposed. In an embodiment,the volume of the bituminous material used to fill the open structure isgreater than a perimeter volume of the base material. In anotherembodiment, the volume of the bituminous material used to fill the openstructure is no greater than the perimeter volume of the base material.

In a particular embodiment, with respect to the base material within thesaturated base material, a portion of a principal surface of the basematerial may be exposed; however, most of the structure or volume of thebase material is embedded within or saturated with the bituminousmaterial used to fill the open structure. Thus, if a ceramic basematerial is scratched or abraded at this point or later in the process,such a scratch or an abrasion will have a lesser effect on theproperties of the finished roofing product, as compared to a roofingproduct where a substantial amount of abrasive particles would liewithin interior portions of the open structure of the ceramic basematerial (e.g., when a substantial amount of abrasive particles, e.g.,fine roofing granules, sand, fiberglass mat particles, etc., fromrecycled roofing articles would be used in the bituminous material).

Advancing to block 108, after filling the open structure of the basematerial, the method can further include applying a coating to aprincipal surface of the base material, where the coating includes thehigh recycled content bituminous material or the low recycled contentbituminous material. The coating can be applied as a film, can beapplied via a lamination technique, or can be applied via anothersuitable process. At decision node 110, a determination can be maderegarding whether an additional coating is to be applied. If noadditional coating is to be applied, the method can proceed to block114.

On the other hand, an additional coating can be applied at block 112.The additional coating can be of the same or different composition asthe coating applied at block 108. Further, more than one coating can beapplied to the same or opposite principal surfaces of the roofingproduct. In a particular example, the coating applied at block 108 caninclude the low recycled content bituminous material, and the additionalcoating can include a coating of filled virgin asphalt mixture, acoating that includes the high recycled content bituminous material, acoating that includes any other amount of recycled roofing material,another coating, or any combination thereof. In another example, thecoating applied at block 108 can include any amount of recycled roofingmaterial, and the additional coating can include the low recycledcontent bituminous material. In yet another example, the additionalcoating applied at block 112 can include a coating formed from the highrecycled content bituminous material and a coating formed from the lowrecycled content bituminous material, where the coating formed from thehigh recycled content bituminous material is disposed between thecoating applied at block 108 and the coating formed from the lowrecycled content bituminous material.

The compositions of the coatings applied at blocks 108 and 112 can beused to increase a thickness of the roofing product, to make the roofingproduct stiffer, to make the roofing product more extensible, to makethe roofing product more impact resistant, or any combination thereof.The additional coating applied in block 112 can provide combinations ofstiffness, extensibility or other synergistic properties that allow aroofing product to have good support characteristics and still maintaingood resistance to damage from objects that hit the roofing product,such as hail or tools dropped onto the roof. Examples of coatings havingdifferent elasticities that together provide combinations of structuralsupport and impact resistance are described in U.S. Patent App. Pub. No.2005/0204675, which is incorporated herein by reference for itsteachings on elasticity and impact resistance. In one embodiment, asheet of the roofing product that is closer to a roofing supportstructure can be more extensible, such that it accommodates impactsthrough its dissipative properties.

In a particular embodiment, the coating applied at block 108 can includea less oxidized region and a more oxidized region before the roofingproduct is installed on a structure. The less oxidized region can bedisposed between the more oxidized region and the base material. In oneexample, the more oxidized region can occupy at least approximately 10%of a thickness of the first coating, such as at least approximately 25%of the thickness of the first coating. In another example, the moreoxidized region can occupy at most approximately 80% of a thickness ofthe first coating, such as at most approximately 50% of the thickness ofthe first coating.

The combination of the base material, the coating applied at block 108and any additional coating comprises a sheet of a roofing product. Aftera last coating is applied at block 108 or 112, the method moves to block114, and a finishing operation is performed on the sheet. The finishingoperation includes applying roofing granules, a parting agent or otherparticles to an exposed surface of the roofing product; applying anadhesive or a release sheet to an exposed surface of the roofingproduct; oxidizing an exposed surface of a coating at a temperaturehigher than a temperature used in forming the coating; exposing anexposed surface of a coating to a source of actinic radiation; anothersuitable finishing operation, or any combination thereof, to an exposedsurface of the roofing product.

In one embodiment, the sheet can include a roofing shingle, and thefinishing operation can include application of roofing granules or otherparticles. Roofing granules can be used for ultraviolet radiationprotection, coloration, aesthetics, impact resistance, fire resistance,another suitable purpose, or any combination thereof. The roofinggranules can include inert base particles that are durable, inertinorganic mineral particles, such as andesite, boehmite, coal slag,diabase, metabasalt, nephaline syenite, quartzite, rhyodacite, rhyolite,river gravel, another suitable inert material, or any combinationthereof. In another embodiment, the roofing granules can includerecycled roofing material particles.

The roofing granules can also include a granule coating over the inertbase particles. A granule coating can cover at least approximately 75%of the surface of the inert base particle, and may cover at leastapproximately 90% of the surface of the inert base particle. In aparticular embodiment, the granule coating continuously covers thesurface of the inert base particle, and such granule coating has asubstantially uniform thickness. If more than one granule coating isused, a subsequent granule coating may cover an underlying granulecoating to the extent described with respect to the inert baseparticles.

If more than one granule coating is used, a granule coating closer tothe inert base particle can include a binder that can be inorganic ororganic. An inorganic binder can include a silicate binder, a titanatebinder, a zirconate binder, an aluminate binder, a phosphate binder, asilica binder, another suitable inorganic binder, or any combinationthereof. An organic binder can include a polymeric compound. In aparticular embodiment, an organic binder can include an acrylic latex,polyurethane, polyester, silicone, polyamide, or any combinationthereof. One or more additional organic binders of the same or differentcomposition can be used.

A granule coating can include an algaecide or another biocide to helpreduce or delay the formation of algae or another organic growth. Thealgaecide or other biocide can include a triazine, a carbamate, anamide, an alcohol, a glycol, a thiazolin, a sulfate, a chloride, aquaternary ammonium compound, copper, a copper compound, zinc, a zinccompound, another suitable biocide, or any combination thereof. In aparticular embodiment, the algaecide or other biocide can be includedwithin an inorganic granule coating binder. For example, the algaecideor other biocide can be included within an alkali metal silicate binder.In another embodiment, the algaecide or other biocide can be includedwithin an organic granule coating binder, such as a polymeric latexbinder. A polymeric latex binder can include polyethylene, a polyolefin,an acid-containing polyolefin, ethylene vinyl acetate, an ethylene-alkylacrylate copolymer, a polyvinylbutyral, polyamide, a fluoropolymer, anacrylic, a methacrylate, an acrylate, polyurethane, another suitablebinder material, or any combination thereof. Alternatively, the bindermay include a solvent-based material, a radiation-curable material, or atwo-part reactive material. These alternative materials may likewiseinclude any of previously described polymeric materials. The same ordifferent algaecide or other biocide can be used within differentgranule coatings. An algaecide or another biocide is not required to bepresent in every granule coating of the roofing granules.

A granule coating can include a solar reflective material that helps toreflect at least some of the solar energy. For example, UV radiation canfurther polymerize or harden the roofing product as the roofing productis exposed outdoors over a long period of time. A solar reflectivematerial can include titanium dioxide, zinc oxide, or the like.Alternatively, the solar reflective material can include a polymericmaterial. In an embodiment, a polymer can include a benzene-modifiedpolymer (e.g., copolymer including a styrene and an acrylate), afluoropolymer, or any combination thereof. Other solar reflectivematerials are described in U.S. Pat. No. 7,241,500 and U.S. PublicationNos. 2005/0072110 and 2008/0220167, all of which are incorporated byreference for their teachings of materials that are used to reflectradiation (e.g., UV, infrared, etc.) from the sun.

A granule coating can include a colorant or another material to providea desired optical effect. The colorant or other material can include ametal oxide compound, such as titanium dioxide (white), zinc ferrite(yellow), red iron oxides, chrome oxide (green), and ultramarine (blue),silver oxide (black), zinc oxide (dark green), or the like. In anotherembodiment, the colorant or other material may not be a metal-oxidecompound. For example, the colorant may include carbon black, zinc oraluminum flake, or a metal nitride.

An additional granule coating may be used for a different purpose notdescribed herein. The additional granule coating can have the samecomposition, a similar composition, or a different composition, ascompared to the granule coating over the inert base particles of theroofing granules. For example, the additional granule coating caninclude a different oxide, nitride, oxynitride, carbide, or anycombination thereof. After reading this specification, skilled artisanswill be able to determine if an additional function or purpose is to beserved by the roofing granules and whether an existing granule coatingor material within a granule coating serves such a function or purposeor if an additional granule coating or an additional material within anexisting granule coating would be needed or desired.

More than one type of roofing granule can be used in a roofing product.Thus, roofing granules can have a characteristic hardness. The hardnessof each roofing granule can be the hardness of the material along anexposed surface of the roofing granule. If no coating is used, thehardness of a particular roofing granule can be the hardness of theinert base particle for that particular roofing granule. If a granulecoating is used, the hardness of the particular roofing granule can bethe hardness of the granule coating lying along the exposed surface ofthat particular roofing granule. For a set of roofing granules, thecharacteristic hardness can be an averaged hardness, such as an average,a geometric mean, or a median. Alternatively, the characteristichardness may be expressed as a percentile. For example, thecharacteristic hardness may be a 10^(th) percentile, 25^(th) percentile,or other percentile value. For a 10^(th) percentile value, thecharacteristic hardness would mean that 10 percent all other roofinggranules are as hard as or harder than a particular hardness. In stillanother embodiment, the characteristic hardness can be the highesthardness for the roofing granules within the set. In another embodiment,the characteristic hardness may be determined using a differentcriterion.

In an embodiment, the roofing granules can make up at leastapproximately 5 weight %, 8 weight %, or 11 weight % of thesubstantially completed roofing product, and in another embodiment, theroofing granules may make up no greater than approximately 60 weight %,50 weight %, or 45 weight % of the substantially completed roofingproduct.

In addition to or in place of applying roofing granules, anotherfinishing operation can be performed. For example, after roofinggranules are applied, another granule coating (not illustrated), similarto any single or combination of binders and granule coatings previouslydescribed with respect to the roofing granules, may be applied onto theroofing product after roofing granules have been applied. Such binder orgranule coating may have a solar reflective property, an algaecide orother biocide, a pigment or another appearance modifier, or anycombination thereof as previously described.

In a particular embodiment, the finishing operation can includedispensing a parting agent onto another exposed surface of the roofingproduct, such as on another principal surface of the base material wherethe roofing product includes a shingle. The parting agent helps to keepthe finished roofing product from sticking to itself on a take-up spoolor sticking to other manufacturing equipment during subsequentmanufacturing. The parting agent can include particles of sand, talc,limestone, slag, another relatively inert material, or any combinationthereof. In another embodiment, the parting agent can include recycledroofing material having a different recycled roofing content as comparedto a coating of the roofing product.

In another embodiment, the finishing operation can include a finishingoperation adapted to oxidize or harden an exposed surface of the roofingproduct. In a particular example, the finishing operation can includeoxidizing an exposed surface of the roofing product at a temperaturehigher than a temperature used in forming an exposed coating of theroofing product. In another example, the finishing operation can includeexposing an exposed surface of the roofing product to a source ofactinic radiation, such as ultraviolet radiation. In a particularembodiment, a lamp or other source may emit radiation at an emissionmaximum below approximately 400 nm. The lamp can be used to expose theroofing product to significantly higher radiation than would be achievedby exposure to the sun or incandescent or fluorescent lights. In anotherembodiment, a source of actinic radiation is an electron beam. In yetanother embodiment, actinic radiation is provided by a gamma radiationsource.

In another example, the finishing operation may include applying achemical hardening agent to an exposed surface of the roofing product.Such hardening agent can include a peroxide, ozone, an acid, a base,another suitable hardening agent, or any combination thereof. In stillanother embodiment, the roofing product can be exposed to anoxygen-containing plasma.

Any or all of the finishing operations described herein may oxidize orfurther crosslink compounds under the treated surface of the roofingproduct. In one embodiment, the thickness of the roofing productaffected may be at least approximately 10% or 25% of the roofingproduct, and in another embodiment, may be at most approximately 80% or50% of the thickness of the roofing product.

In still another embodiment, no finishing operation may be performed,only one or some, but not all, of the previously-described finishingoperations may be performed, or another finishing operation may beperformed in addition to or in place of another finishing operation aspreviously described. In this shingle manufacturing embodiment, astamping or other apparatus may be used to transform the roofing productinto shingles. In a particular embodiment, the roofing product on thetake-up spool can be moved to another apparatus so that shingles can bestamped out of the material. Alternatively, the take-up spool may not beused, and a stamping stage may be used in its place. After reading thisspecification, skilled artisans will be able to configure amanufacturing line for the particular roofing product being formed.

In another embodiment, the roofing product can include a membrane-typeroofing product. The membrane-type roofing product is typically aself-adhesive product, although this is not a requirement. Roofinggranules may or may not be dispensed onto the membrane-type roofingproduct. The membrane-type roofing product may be applied directly to aroof deck as a base sheet or an underlayment. In this particularapplication, an adhesive can be applied to the other side of the basematerial (the side opposite the coating). The adhesive can be used toprovide a good seal to help reduce the likelihood of water damage fromice dams. The adhesive can include a tackifier, such aspolyvinylbutyral, a pressure sensitive adhesive, another suitablecompound, or any combination thereof. A pressure sensitive adhesive caninclude a silicone, a rubber, an acrylate, or the like. In a particularembodiment, a styrene-isoprene-styrene rubber composition can be used.In another particular embodiment, a polymer-modified bitumen adhesivecan be used. A release sheet can be applied to the adhesive, such thatthe adhesive is disposed between the release sheet and the basematerial.

In an alternative embodiment, an adhesive modifier can be added to thelow recycled content or high recycled content bituminous material withina coating of the membrane-type roofing product that is to contact astructure. Thus, a separate adhesive application operation may beeliminated. In this particular embodiment, the release sheet would beapplied to the surface having the adhesive-modified bituminous material.

FIGS. 4 to 6 include exemplary, non-limiting embodiments of roofingproducts that can be made, for example, using the process described withrespect to FIG. 1. FIG. 4 illustrates a cross-sectional view of aroofing product 400 that includes a base 402 in which a material isembedded or saturated within the open structure of a base material, suchas a fiberglass mat or another base material. If the base 402 providesprincipal support, such as when the roofing product 400 is a finishedroofing product, the bituminous material used to fill the open structuredepends on the base material. For instance, if the base material isfiberglass and the base 402 provides principal support for the roofingproduct 400, a non-abrasive material can be used to fill the openstructure, in order to prevent scratching of the fiberglass. Forexample, limestone particles, talc, clay, non-abrasive coal fines,gypsum, calcite, roofing granules in amounts described with respect toFIG. 1, virgin asphalt or filled virgin asphalt mixture, another similarmaterial, or any combination thereof can be used with a fiberglass matproviding principal support for the roofing product.

Alternatively, if the base material includes a harder material (such as,alumina or another material) or does not provide principal support forthe roofing product 400, a relatively more abrasive material can be usedto fill the open structure of the base 402. For instance, limestoneparticles, sand, the low recycled content bituminous material, the highrecycled content bituminous material, roofing granules, other similarabrasive filler materials, or any combination thereof, can be used as tofill the open structure of the base 402.

A coating 404 is disposed on a principal surface of the base 402. Thecoating 404 can include low recycled content roofing material. Roofinggranules 406 or other particles adapted to produce friction or toprotect a bituminous coating can be disposed on an exposed surface ofthe coating 404, such that the coating 404 is disposed between theroofing granules 406 and the base 402. In another embodiment (notillustrated), the roofing product 400 may be used as an underlayment,such that roofing granules 406 are not used. In a particular embodiment,the roofing product 400 can include a roofing membrane, and an adhesive408 can be disposed on another principal surface of the base 402. Arelease sheet 410 can be disposed on a surface of the adhesive 408 thatis opposite the base 402.

In another embodiment, the base 402 and the coating 404 can togetherconstitute a sheet that may be combined with other sheets, as describedin further detail later in this specification. Where the base 402 andthe coating 404 constitute such a sheet, the roofing granules 406, theadhesive 408, the release sheet 410, or any combination thereof can beeliminated from, or otherwise not used in, the roofing product 400.

FIG. 5 includes in illustration of a cross-sectional view of anotherroofing product 500. The roofing product 500 includes a base 502 inwhich a material is embedded or saturated within the open structure of aceramic base material or other base material. An abrasive property ofthe material used to fill the open structure can depend on a hardness ofthe base material used in the base 502. A plurality of coatings 504 and512 are disposed on the base 502. For example, an intermediate coating512 can be disposed on a principal surface of the base 502 and can bedisposed between the base 502 and the coating 504.

In one embodiment, the coating 504 can include low recycled contentbituminous material, and the intermediate coating 512 can include thehigh recycled content bituminous material or can include a coating thatcontains any amount of recycled roofing material, such as less thanapproximately 80 weight % of recycled roofing material, less thanapproximately two-thirds by weight of recycled roofing material, lessthan approximately 50 weight % of recycled roofing material, less thanapproximately one-third by weight of recycled roofing material, or norecycled roofing material.

Roofing granules 506 or other particles adapted to produce friction orto protect a bituminous coating can be disposed on an exposed surface ofthe coating 504, such that the coating 504 is disposed between theroofing granules 506 and the intermediate coating 512. In anotherembodiment (not illustrated), the roofing product 500 may be used as anunderlayment, such that roofing granules 506 are not used. In aparticular embodiment, the roofing product 500 can include a roofingmembrane, and an adhesive 508 can be disposed on another principalsurface of the base 502. A release sheet 510 can be disposed on asurface of the adhesive 508 that is opposite the base 502.

In another embodiment, the base 502 and the coatings 504 and 512 cantogether constitute a sheet that may be combined with other sheets, asdescribed in further detail later in this specification. Where the base502 and the coatings 504 and 512 constitute such a sheet, the roofinggranules 506, the adhesive 508, the release sheet 510, or anycombination thereof can be eliminated from, or otherwise not used in,the roofing product 500.

FIG. 6 illustrates a cross-sectional view of yet another roofing product600 in the form of a shingle. The roofing product 600 includes a base602 in which a material is embedded or saturated within the openstructure of a base material. A coating 604 is disposed on a principalsurface of the base 602. The coating 604 can include low recycledcontent bituminous material.

In another embodiment (not shown), the roofing product 600 can include aplurality of coatings. For instance, an additional coating may overlaythe coating 604, such that the coating 604 is disposed between theadditional coating and the base 602. In a further example, coatings thatinclude the low recycled content bituminous material can be disposed ona plurality of principal surfaces of the base 602. In another example, acoating that includes the low recycled content bituminous material canbe disposed on a side of the base 602 and another coating having anyamount of recycled roofing material, or no recycled roofing material,can be disposed on another principal surface of the base 602. In stillanother example, an intermediate coating can be disposed between thebase 602 and a coating of low recycled content bituminous materialdisposed on a principal surface, or a plurality of principal surfaces,of the base 602. Those skilled in the art will recognize that manycombinations of coatings can be applied to one or both sides of the base602 in addition to the coating 604 that includes low recycled contentbituminous material.

Roofing granules 606 or other particles adapted to produce friction orto protect a bituminous coating can be disposed on an exposed surface ofthe coating 604, such that the coating 604 is disposed between theroofing granules 606 and the base 602. In a particular embodiment, theroofing product 600 can include a shingle, and a parting agent 616 canbe disposed on another side of the base 602. The parting agent 616 isadapted to prevent the finished roofing product from sticking to itselfon a take-up spool, for example, or sticking to other manufacturingequipment during subsequent manufacturing, or in a stack of bundledshingles. The parting agent 616 can include particles of sand, talc,limestone, slag, another relatively inert material, or any combinationthereof.

In another embodiment, the base 602 and the coating 604 can togetherconstitute a sheet that may be combined with other sheets, as describedin further detail later in this specification. Where the base 602 andthe coating 604 constitute such a sheet, the roofing granules 606, theparting agent 616, or any combination thereof can optionally beeliminated from, or otherwise not used in, the roofing product 600.

FIG. 7 includes a process flow diagram illustrating an exemplary methodof forming a laminated roofing product including a plurality of sheets.At block 702, a plurality of sheets is formed, each sheet having a basematerial and a coating. The coating can include the low recycled contentbituminous material. In one embodiment, a sheet may be formed accordingto the process described with respect to FIG. 1. Each sheet may besimilar to those roofing products 400, 500, or 600 illustrated in FIGS.4-6. However, a sheet may or may not include a finishing component, suchas roofing granules, an adhesive, a parting agent, a release sheet, orany combination thereof, before lamination.

Moving to block 704, a pre-lamination operation can be performed withrespect to one or more of the sheets provided at block 702. Thepre-lamination operation can include, for instance, heating a sheet,heating a coating on a sheet, heating a base of a sheet, or anycombination thereof; applying an adhesive to a side of a sheet that willcontact another sheet during lamination; slitting or otherwise cutting asheet; cleaning using water or another solvent; adding a primer to asheet; moving a sheet to align with another sheet to which the sheetwill be laminated; another pre-lamination process; or any combinationthereof. In another embodiment (not shown), no pre-lamination operationcan be performed.

Proceeding to block 706, the sheets are laminated together to form alaminated roofing product. Laminating the sheets can include adheringthe sheets together; curing an adhesive or other material disposedbetween the sheets; vacuum laminating the sheets together; contacting abase or coating of a sheet with a heated coating or base of anothersheet; applying a positive pressure to a sheet to keep it in contactwith another sheet while the sheet, the other sheet, or any combinationthereof, are heated or partially fluid; another laminating process; orany combination thereof. Examples of laminating roofing sheets aredisclosed in U.S. Patent App. Pub. No. 2006/0265990, which isincorporated herein for its teachings on lamination processes.

Continuing to block 708, a post-lamination operation can be performed onthe laminated product, such as those described with respect to finishingoperations at block 114 in FIG. 1. In another embodiment (not shown), nopost-lamination operation can be performed.

FIG. 8 includes an illustration of a cross-sectional view of sheets ofintermediate roofing product before the sheets are laminated togetherinto a laminated roofing product in accordance with an embodiment. Forinstance, a sheet 801 can include a base 802 and a coating 804, andanother sheet 821 can include another base 822 and another coating 824.The sheets 801 and 821 can be laminated together to form a laminatedproduct, such as the laminated roofing product 900 illustrated in FIG.9, wherein a base, such as the base 822 provides principal support forthe roofing product and the base 802 does not provide principal supportfor the roofing product. In this embodiment, the open structure of thebase 822 can be filled with a non-abrasive material if the base 822includes fiberglass, for example, and the open structure of the base 822can be filled with an abrasive material if the base 822 includes aharder material, such as alumina. Further, the open structure of thebase 802 can be filled with an abrasive material or a non-abrasivematerial, as the base 802 does not provide principal support for thelaminated roofing product 900 and will not cause significant failure ofthe laminated roofing product 900 if the base material used in the base802 is scratched by a material used to fill its open structure. Inanother embodiment, the base 802 can be filled with a non-abrasivematerial and the base 822 can be filled with abrasive material, such asrecycled material, where the base 822 is included in an unexposedportion of the laminated roofing product 900.

In an illustrative embodiment, the laminated roofing product 900 caninclude roofing granules 906 on an exposed surface of the laminatedroofing product 900. Additionally, where the laminated roofing product900 is included in a roofing membrane, the laminated product can includean adhesive 908 and a release sheet 910. In another embodiment (notshown), the laminated roofing product 900 can include a roofing shingleand can include a parting agent. Other finishing operations may beperformed on the laminated roofing product 900, as previously describedwith respect to finishing operations at block 114 in FIG. 1.

After reading this specification, skilled artisans will appreciate thatmany other roofing products can be made using the concepts as describedherein. The particular materials, coatings, processes, and otherparameters can be tailored for the roofing products that are needed ordesired.

Embodiments as described herein can be used to produce a roofing productthat includes complementary coatings, wherein each coating provides aparticular benefit, whereas another coating compensates for a detrimentassociated with the coating that provides the particular benefit. Forexample, bituminous material containing recycled roofing material helpsto reduce the need for asphalt made from crude oil and potential landfill space occupied by old roofing materials from a structure that wastorn down or re-roofed. However, high recycled content bituminousmaterial forms a coating that may be stiffer and more brittle thanroofing material that only includes virgin asphalt as its asphaltsource. Low recycled content bituminous material can have a lowercontent of or no recycled roofing articles, more virgin asphalt orfilled virgin asphalt mixture, a higher additive chemicals content(particularly, a plasticizer), or any combination thereof. Thus, the lowrecycled content bituminous material forms a coating that can be lessstiff or brittle or more pliable. Nonetheless, the low recycled contentbituminous material may use more virgin asphalt or filled virgin asphaltmixture, use more plasticizer, be more expensive as compared to the highrecycled content bituminous material, or any combination thereof. Thesynergistic combination of the coatings can allow for a relatively lowercost roofing product to be formed that has acceptable impact resistance.Although two different types of coatings have been described, anadditional type or still a different type of coating can be used withinthe roofing product to achieve desired properties.

As previously mentioned, embodiments can be used to help reduce waste.By recycling roofing articles, the roofing articles may be used to makenew roofing products, rather than occupying valuable space within alandfill. Because roofing articles biodegrade relatively slowly, anyreduction of roofing articles in a landfill helps the environment. Stillfurther, roofing products produced with recycled roofing material may beless costly to produce. As the price of crude oil increases, the priceof virgin asphalt also increases. Unlike virgin asphalt, the price ofthe roofing articles may slowly increase as environmental concerns mayforce scrapped roofing articles to be recycled. Thus, embodiments asdescribed herein allow roofing products to be made at a lower cost ascompared to roofing products formed without any recycled roofingarticles.

Many different aspects and embodiments are possible. Some of thoseaspects and embodiments are described below. After reading thisspecification, skilled artisans will appreciate that those aspects andembodiments are only illustrative and do not limit the scope of thepresent invention.

In a first aspect, a roofing product can include a base material and afirst coating adjacent to the base material. The first coating caninclude a recycled roofing material and the recycled roofing materialcan have a first recycled roofing content of less than 40 weight %. Inan embodiment of the first aspect, the roofing product can include abituminous material. The base material can include an open structure,and the bituminous material can substantially fill the open structure.

In another embodiment of the first aspect, the roofing product caninclude a second coating disposed between the first coating and the basematerial. The second coating can have a second recycled roofing contentdifferent from the first recycled roofing content.

In a further embodiment of the first aspect, the roofing product caninclude particles along an exposed surface of the roofing product. Theparticles can include recycled roofing particles.

In an additional embodiment of the first aspect, the roofing product caninclude an adhesive compound and a release sheet. The adhesive compoundcan be disposed between the base material and the release sheet, and thebase material can be disposed between the first coating and the adhesivecompound.

In another embodiment of the first aspect, before the roofing product isinstalled on a structure, the first coating can have a less oxidizedregion and a more oxidized region. The less oxidized region can bedisposed between the more oxidized region and the base material, and themore oxidized region can occupy at least approximately 10% of athickness of the first coating.

In yet another embodiment of the first aspect, the roofing product caninclude a parting agent disposed on another principal surface of thebase material. The base material can be disposed between the firstcoating and the parting agent. The parting agent can include anotherrecycled roofing material having a second recycled roofing contentdifferent from the first recycled roofing content.

According to a second embodiment, a roofing product can include a basematerial and a first coating including a bituminous material. The firstcoating can be adjacent to the base material. The roofing product canalso include roofing granules along a first exposed surface of theroofing product. The roofing granules can include recycled roofingmaterial particles.

In an embodiment of the second aspect, the roofing product can include abituminous material substantially free of abrasive particles. The basematerial can include a ceramic base material having an open structure,and the bituminous material substantially fills the open structure.Further, a second coating can be disposed between the first coating andthe base material, where the second coating includes a recycled roofingcontent.

In another embodiment of the second aspect, the roofing product caninclude other particles along another exposed surface of the roofingproduct opposite the first exposed surface, wherein the other particlesinclude recycled roofing particles.

In another embodiment of the second aspect, the roofing product caninclude an adhesive compound and a release sheet. The adhesive compoundcan be disposed between the base material and the release sheet, and thebase material can be disposed between the first coating and the basematerial.

In a further embodiment of the second aspect, before the roofing productis installed on a structure, the first coating can have a less oxidizedregion and a more oxidized region. The less oxidized region can bedisposed between the more oxidized region and the base material, and themore oxidized region can occupy at most approximately 80% of a thicknessof the first coating.

According to a third aspect, a method of forming a roofing product caninclude providing a base material and forming a first coating adjacentto the base material. The first coating can include a recycled roofingmaterial, and the recycled roofing material can have a first recycledroofing content of less than 40 weight %.

In an embodiment of the third aspect, the base material can include aceramic base material having an open structure, and the method canfurther include filling the open structure of the ceramic base materialwith a bituminous material before forming the first coating. Thebituminous material can be substantially free of abrasive particles.

In another embodiment of the third aspect, the method can includeforming a second coating adjacent to the base material before formingthe first coating. The second coating can have a second recycled roofingcontent different from the first recycled roofing content.

In a further embodiment of the third aspect the method can includeforming a second coating adjacent to the base material. The secondcoating can have a second recycled roofing content different from thefirst recycled roofing content, and in a finished roofing product, thebase material can be disposed between the first and second coatings.

In another embodiment of the third aspect, the method can includeapplying particles along an exposed surface of the roofing product afterforming the first coating. The particles can include recycled roofingmaterial particles.

In another embodiment of the third aspect, the method can includeapplying an adhesive along an exposed surface of the roofing productafter forming the first coating.

In yet another embodiment of the third aspect, the method can includeoxidizing an exposed surface of the first coating at a temperaturehigher than a temperature used in forming the first coating.

In still another embodiment of the third aspect, the method can includeexposing an exposed surface of the first coating to a source of actinicradiation.

According to a fourth aspect, a method of forming a roofing product caninclude providing a base material and forming a first coating includinga bituminous material, where the first coating is adjacent to the basematerial. The method can also include applying particles along a firstexposed surface of the roofing product after forming the first coating.The particles can include recycled roofing material particles.

In an embodiment of the fourth aspect, the base material can include aceramic base material having an open structure, and the method caninclude filling the open structure of the ceramic base material with abase bituminous material before forming the first coating. The basebituminous material can be substantially free of abrasive particles.

In another embodiment of the fourth aspect, the method can includeforming a second coating adjacent to the base material, before formingthe first coating, and the second coating can have a recycled roofingcontent.

In another embodiment of the fourth aspect, the method can includeapplying an adhesive along an exposed surface of the roofing productafter forming the first coating.

In another embodiment of the fourth aspect, the method can includeoxidizing an exposed surface of the first coating at a temperaturehigher than a temperature used in forming the first coating.

In another embodiment of the fourth aspect, the method can includeexposing an exposed surface of the first coating to a source of actinicradiation.

Note that not all of the activities described above in the generaldescription or the examples are required, that a portion of a specificactivity may not be required, and that one or more further activitiesmay be performed in addition to those described. Still further, theorder in which activities are listed is not necessarily the order inwhich they are performed.

Benefits, other advantages, and solutions to problems have beendescribed above with regard to specific embodiments. However, thebenefits, advantages, solutions to problems, and any feature(s) that maycause any benefit, advantage, or solution to occur or become morepronounced are not to be construed as a critical, required, or essentialfeature of any or all the claims.

The specification and illustrations of the embodiments described hereinare intended to provide a general understanding of the structure of thevarious embodiments. The specification and illustrations are notintended to serve as an exhaustive and comprehensive description of allof the elements and features of apparatus and systems that use thestructures or methods described herein. Separate embodiments may also beprovided in combination in a single embodiment, and conversely, variousfeatures that are, for brevity, described in the context of a singleembodiment, may also be provided separately or in any subcombination.Further, reference to values stated in ranges includes each and everyvalue within that range. Many other embodiments may be apparent toskilled artisans only after reading this specification. Otherembodiments may be used and derived from the disclosure, such that astructural substitution, logical substitution, or another change may bemade without departing from the scope of the disclosure. Accordingly,the disclosure is to be regarded as illustrative rather thanrestrictive.

1. A roofing product comprising: a base material; and a first coatingadjacent to the base material, the first coating including a recycledroofing material, wherein the recycled roofing material has a firstrecycled roofing content of less than 40 weight %.
 2. The roofingproduct of claim 1, further comprising a bituminous material, whereinthe base material includes an open structure, and the bituminousmaterial substantially fills the open structure.
 3. The roofing productof claim 1, further comprising a second coating disposed between thefirst coating and the base material, wherein the second coating has asecond recycled roofing content different from the first recycledroofing content.
 4. The roofing product of claim 1, further comprisingparticles along an exposed surface of the roofing product, wherein theparticles include recycled roofing particles.
 5. The roofing product ofclaim 1, further comprising an adhesive compound and a release sheet,wherein the adhesive compound is disposed between the base material andthe release sheet, and the base material is disposed between the firstcoating and the adhesive compound.
 6. The roofing product of claim 1,wherein before the roofing product is installed on a structure, thefirst coating has a less oxidized region and a more oxidized region,wherein the less oxidized region is disposed between the more oxidizedregion and the base material, and the more oxidized region occupies atleast approximately 10% of a thickness of the first coating.
 7. Theroofing product of claim 1, further comprising a parting agent disposedon another principal surface of the base material, wherein the basematerial is disposed between the first coating and the parting agent. 8.The roofing product of claim 7, wherein the parting agent includesanother recycled roofing material having a second recycled roofingcontent different from the first recycled roofing content. 9-14.(canceled)
 15. A method of forming a roofing product comprising:providing a base material; and forming a first coating adjacent to thebase material, wherein the first coating includes a recycled roofingmaterial, wherein the recycled roofing material has a first recycledroofing content of less than 40 weight %.
 16. The method of claim 15,wherein: the base material includes a ceramic base material having anopen structure; and the method further includes filling the openstructure of the ceramic base material with a bituminous material beforeforming the first coating, wherein the bituminous material issubstantially free of abrasive particles.
 17. The method of claim 15,further comprising forming a second coating adjacent to the basematerial before forming the first coating, wherein the second coatinghas a second recycled roofing content different from the first recycledroofing content.
 18. The method of claim 15, further comprising forminga second coating adjacent to the base material, wherein the secondcoating has a second recycled roofing content different from the firstrecycled roofing content, and in a finished roofing product, the basematerial is disposed between the first and second coatings.
 19. Themethod of claim 15, further comprising applying particles along anexposed surface of the roofing product after forming the first coating,wherein the particles include recycled roofing material particles. 20.The method of claim 15, further comprising applying an adhesive along anexposed surface of the roofing product after forming the first coating.21. The method of claim 15, further comprising oxidizing an exposedsurface of the first coating at a temperature higher than a temperatureused in forming the first coating.
 22. The method of claim 15, furthercomprising exposing an exposed surface of the first coating to a sourceof actinic radiation.
 23. A method of forming a roofing productcomprising: providing a base material; forming a first coating includinga bituminous material, wherein the first coating is adjacent to the basematerial; and applying particles along a first exposed surface of theroofing product after forming the first coating, wherein the particlesinclude recycled roofing material particles.
 24. The method of claim 23,wherein: the base material includes a ceramic base material having anopen structure; and the method further includes filling the openstructure of the ceramic base material with a base bituminous materialbefore forming the first coating, wherein the base bituminous materialis substantially free of abrasive particles.
 25. The method of claim 23,further comprising forming a second coating adjacent to the basematerial, wherein the forming the second coating is performed beforeforming the first coating, and the second coating has a recycled roofingcontent.
 26. The method of claim 23, further comprising applying anadhesive along an exposed surface of the roofing product after formingthe first coating. 27-32. (canceled)
 33. The roofing product of claim 6,wherein the more oxidized region occupies at most approximately 80% of athickness of the first coating. 34-40. (canceled)
 41. The roofingproduct of claim 1, further comprising a bituminous materialsubstantially free of abrasive particles, wherein the base materialincludes a ceramic base material having an open structure, and thebituminous material substantially fills the open structure.
 42. Theroofing product of claim 1, wherein the roofing product is amembrane-type roofing product.
 43. The roofing product of claim 1,wherein the roofing product is a shingle-type roofing product.